1. Field of the Invention
Combustion engine accessories
2. Description of the Prior Art
Occasionally a descriptive term in this application may be shortened so as to recite only a part rather than the entirety thereof as a matter of convenience or to avoid needless redundancy. In instances in which that is done, applicant intends that the same meaning be afforded each manner of expression. Thus, the term threaded needle advancement and retraction adjusting tunnel (42) might be used in one instance but in another, if meaning is otherwise clear from context, expression might be shortened to needle adjusting tunnel (42) or merely tunnel (42). Any of those forms is intended to convey the same meaning.
The word comprise may be construed in either of two ways herein. A term used to describe a given object is said to comprise it, thereby characterizing it with equivalency in meaning for the term. Thus, FIGS. 3-6 may be said to comprise views of a carburetion adjusting assembly, meaning that in the particular case, each of the drawings is such a view. However, the word comprise may also be used to describe a feature which is part of the structure or composition of a given element or assembly. Thus, an adjusting tunnel (42) may be said to comprise an external port (44), meaning that the structure of the adjusting tunnel (42) is such as to have the external port (44) as a feature of its (42) structure. The meaning in the respective cases is clear from context, however. Accordingly, modifying words to clarify which of the two uses is the intended one seem unnecessary.
Terms relating to physical orientation such as up, down, higher and lower refer to carburetion assembly positioning in the manner in which it is typically observed in a vehicle and consistent with the manner the subjects of this application are shown in the drawings. Thus, an interference needle stop (50), the positioning of which (50) when present is affected by the adjustment means featured herein, is spoken of as being disposed atop a spacing spring shoulder (51).
Typically, carburetors comprise a sliding mechanism-an airflow obstructor (400)xe2x80x94controlled operationally by retraction or extension of a throttling cable (500). The cable (500) is configured with anchoring meansxe2x80x94not specifically addressed herein but part of another divisionalxe2x80x94so that when retracted, the airflow obstructor (400) is tugged open to allow therethrough the passage of air. The mixture of air and fuel is ducted to the engine""s combustion chambers.
It is generally recognized that carburetors comprise performance characteristics ranging from low level to high level, corresponding with cross-sectional airflow access area causally associated with throttling cable (500) disposition ranging from idling status to full retraction.
Although carburetion has been known since the last century, the never ending search for better efficiency and improved performance continues today.
Despite several historical redesign undertakings and the expectation that performance should increase proportionately to operable throttle advance, carburetion problems remain. It has been observed that the rate of increase levels off or even drops when engine throttling is taken to the higher range. In stressed circumstances such as mountain driving where the air is thinner, the problems become aggravated. Acquiring a larger carburetor to address them unfortunately results in a tradeoff at mid and lower range carburetion levels.
In sports vehicles-snowmobiles and speedboats, for examplexe2x80x94carburetor designs providing not only for constancy of efficiency at all carburetion stages but as well for quick acceleration response throughout all levels of operation are constantly sought after. Operational readjustments may be made, of course, to accommodate the problems as they arise during vehicle use. It is not an uncommon experience for an operator to contend with sluggish performance by spending 20 minutes resetting or retuning the carburetor by disassembling and adjusting parts which are virtually inaccessible. The task with snowmobiles is complicated by adverse winter conditions and with boats by buoyant instability upon the water. If attempted with a snowmobile in a remote area, as it sometimes is, the loss of even one of the tiny components can be disastrous.
The needs or objectives pointed out supra thus far remain only partly addressed in the prior art. Some, such as that just immediately addressed, have not been met at all.
The invention is a distinct carburetor feature providing improved performance, comprising easily accessible needle advancement and retraction adjustment means.
The needle advancement and retraction means (42, 44-49, 53) simplify access to and adjustment of the position of a fuel flow interference needle (900) with reference to the needling fuel jet (800), an otherwise laborious and time consuming task at prior art.
This feature, working in conjunction with others not the subject hereof dramatically enhances engine performance for all engines in general and provides, in particular, excitement for operators of sports vehicles.